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Friday, March 27, 2015

I don’t have
much experience pruning trees other than removing low branches.Most large yard trees can be treated with
benign neglect.Fruit trees are another
thing altogether.Shaping the tree
properly in its early years can have a strong impact on its capacity to bear
fruit later on.I wanted to get it
right, but for a novice like me pruning a young apple tree is like driving at
night with the headlights off.

I planted
two apple trees three years ago (I think), a Golden Delicious and a Fuji.They were in pots and had some lateral
branches on the main stem.The Golden
Delicious is now about 10 feet tall, while the Fuji, with a central leader, is
more than 12 feet in height.I’ve made
attempts over the years to shape their growth by removing some lateral branches
and vertical growth.This year I realized
that both trees needed a more aggressive pruning to shape their growth as they
approach maturity.

The thing
about pruning to consider is not what the tree looks like just after it is
pruned, because at the end of the growing season it will look quite a bit
different.The manner in which the tree
is pruned affects the manner in which it grows.One has to envision what a pruning cut will produce in branches in the years
to come.

I checked
out some books from the library on pruning, some helpful, others not at all.Currently many resources recommend a central
leader tree with the largest branches low and smaller branches high for maximum
fruit production, assuming I guess that the rootstock the tree is grafted to
will prevent the tree from growing excessively tall.Two or three whorls of well-spaced scaffold
laterals are allowed to establish themselves.Unfortunately the tree rarely cooperates with the ideal.

I already
knew that trees grow at their tips to increase length and the phloem layer just
beneath the bark produces wood and adds girth.Trees don’t grow out of the ground and a branch always remains at its
initial height on the trunk.During the
winter chemical energy is stored in the roots and in the springthe sap moves up to feed the opening buds.Pruning removes buds, meaning that as sugars
move up the tree in spring the chemical energy is distributed to fewer buds.It seems counterintuitive, but a weak branch
will grow more if pruned more severely than a strong branch.

While
pruning new growth back a few buds will stimulate growth, completely removing a
branch at the branch collar ends that branch for good.However, if you leave a short stub that
branch may well start a new bud and ultimately a new replacement branch.This branch was removed because there were two branches arising at the same height of the trunk.

Two weeks ago with cutting tools in hand I set about pruning both trees.The Golden Delicious tree is something of a
problem tree.It has a large lower side
branch at about a 45 degree angle, really not enough, although the crotch
appears solid.Maybe I should have
removed it early on, but there were few other scaffold branches to work with so I left it
on.This is the tree before pruning. It had a large number of watersprouts and crossing branches from last year's growth.

Last
year this tree lost its central leader.A high branch came off the leader at an acute angle and I planned to cut
this branch off when the tree went dormant, but circumstances forced my hand. Last summer I was trying to spray the leader
with some Neem oil and as I was pulling down the leader to spray its leaves the
crotch broke. The leader tore off, leaving the uppermost branch and a large gash in the trunk. The tear has healed partially but it may not heal strong enough to support the weight above it. Next winter I'll decide whether to remove the topmost branch entirely.

This is the
same tree after pruning.It looks
severe, but most of the mass of the tree remains.With the central leader gone, the tree is
best described as a half-standard.In
all likelihood the uppermost branch will have to be cut off below the wound but
I felt that, for this year, enough wood had been removed.

The Fuji has
a much better fan shape and was easier to prune, although some thinning was
needed. Many of the laterals were too closely spaced had
to be removed.You can’t see it well in
this picture since the shot doesn't go high enough, but an upper branch matched the central leader in height and one
of them had to go, otherwise the tree would have two leaders.

This is the
same tree after pruning. I tried to thin out the upper branches more in order
to let light into the lower branches.The central leader is reaching for the skies, and it may well have to be
removed because it will be hard to reach apples up there.It looks like the tree will flower this year
and produce a few apples.For the time
being I’ll leave the leader in place, and see if the first years’ fruit
production will stop the vertical growth.Any reader’s suggestions are welcome.

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About this Blog

I moved to this place in SW Indiana in 2008. The property is six acres of woods, pasture, yard and pond. Usable garden space with full sun is limited by surrounding trees to 250 square feet of raised beds, more the size of an urban garden. I use intensive techniques: rotation of plant families, nutrient cycling, cages and trellises, row cover and cold frames to get the most out of the space.

About Me

A native Hoosier, I worked in the construction trades and later in life got a chemistry degree and worked in a research lab until retirement. I raise vegetables because they taste better and it saves money. What other hobby pays for itself? I'm a cheapskate - I won't buy new seeds until the old ones aren't any good. I'm also a bit of a lazy gardener - if I can buy the seedlings I want then why start the seeds, or if I can engineer a way to make it less work I'll do so. I also drink too much beer. But I never (well almost never) work in the garden and drink beer.